Reward processing is a crucial component of decision making and has implications for risk taking behavior, mood disorders, and substance abuse. Adolescence is a period of development when risk taking behavior peaks and mood disorders and substance abuse can emerge. We do not yet have a clear understanding of how reward and punishment alter behavior in adolescence. We have even less of an understanding of how reward/punishment influences the brain circuitry that is recruited to make decisions at this developmental stage. We propose to study 120 ten to 20 year-old healthy subjects in a hybrid longitudinal/cross-sectional design that spans ten years of development. We will assess the developmental changes related to the effects of monetary incentives on the ability to suppress task inappropriate responses, using eye movements as a model system. Using fMRI, we will investigate developmental changes in the recruitment of frontostriatal circuitry supporting reward/punishment processing and characterize how these affect known mechanisms supporting cognitive control. Diffusion Tensor Imaging (DTI) will be used to assess the contribution of myelination to observed changes in the recruitment of frontostriatal circuitry and subsequent behavioral changes with development. Associations between these results and age, pubertal status, gender, and sensation seeking indices will be investigated to account for individual variability in developmental trajectories. This work will result in a normative template of the maturation of reward/punishment processes through adolescence, a critical step toward understanding vulnerabilities in the adolescent brain for risk taking behavior, mood disorders, and substance abuse. PUBLIC HEALTH RELEVANCE: Adolescence is a period marked by an increase in risk-taking behavior (substance abuse, unprotected sex, extreme sports) that has lead to a strikingly high mortality rate. Additionally, most major psychiatric illnesses emerge during the period of transition from adolescence to adulthood. We propose studies that can inform these literatures by providing information regarding the limitations and vulnerabilities in brain processing present in adolescence and how these affect reward assessment and decision making.